On Tue, Nov 26, 2013 at 04:55:50PM -0800, Ben Widawsky wrote: > If we end up calling the shrinker, which in turn requires the OOM > killer, we may end up infinitely waiting for a process to die if the OOM > chooses. The case that this prevents occurs in execbuf. The forked > variants of gem_evict_everything is a good way to hit it. This is > exacerbated by Daniel's recent patch to give OOM precedence to the GEM > tests. > > It's a twisted form of a deadlock. > > What occurs is the following (assume just 2 procs) > 1. proc A gets to execbuf while out of memory, gets struct_mutex. > 2. OOM killer comes in and chooses proc B > 3. proc B closes it's fds, which requires struct mutex, blocks > 4, OOM killer waits for B to die before killing another process (this > part is speculative) > > Cc: Daniel Vetter <daniel.vetter@xxxxxxxx> > Cc: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> > Signed-off-by: Ben Widawsky <ben@xxxxxxxxxxxx> I'd still like to know if I am crazy, but I'm now trying to defer the stuff we do on file close without using any allocs. Just an update... -- Ben Widawsky, Intel Open Source Technology Center _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx
